Device for plugging oil wells



May 29, 1928,

N. G. .BRITTON DEVICE FOR PLUGGING OIL WELLS Filed 001.. 18, 1927 Patented May 29, 1928.

1,671,223 PATENT OFFICE.

NATHAN' GFF BRITTON, OF NEWBERNE, WEST VIRGINIA.

DEVICE FOR PLUGGING OIL WELLS.

Application filed October 18, 1927. Serial No. 226,961.

This invention relates to devices for plugging oil wells and has for an important object thereof the provision of a device of this character which will provide an effective and thorough seal of the well.

As is well known to those familiar with.

the art, oil well plugs have hitherto been of two different types. The first and mostcommonly employed type is: a rubber plug which, when inserted in the well, is expanded against the walls of the casing to provide the necessary seal. The second is a soft l metal plug which is expanded by a mandrel. Each of these types is possessed of faults which render it impractical.` The rubber packer has a tendency to deteriorate after being in the well a short time and if there is any substantial gas pressure, will be blown out or the deterioration will result in leakage. The soft metal plug, while affording when expanded suicient resistance to prevent blowing out, is not capable of producing an absolutely tight seal, so that there is always a small seepage or pressure leak thereabout. Accordingly, an important object of the present invention is the provision of a plugging structure which will not leak or blow out and accordingly provides a permanent seal for the well.

These and other objects I attain by the construction shown in the accompanying drawings, wherein for the purpose of illustration is shown a preferred embodiment of my invention and wherein Figure l is a vertical sectional viewv through well plugging apparatus constructed in accordance with my invention showing the parts in the position which they occupy when the device is lowered into'the well;

Figure 2 is a similar view showing lthe parts in their operative or packing posit-ion.

Referring now more particularly to the drawings, the numeral generally designates the bottom of a well bore and 11 a casing arranged within the bore. In accordance with my invention, I provide a tube 12, the lower end of which is sealed and adapted for engagement with the well bottom 10, being preferably made relatively heavy, as illustrated. Secured within this tube are a plurality of bent spring fingers 13 havingtheir upper outer ends secured to the tube wall, as at 14, and their inner free ends 15 arranged at different levels within plug 25.

the tube. The upper end of the tube threads into an annulus 16 having an up-l standing lange 17 upon which is seated the lower end of a rubber packer 18. This rubber packerhas a bore 19 for the reception of a tapered mandrel 20 and the lower end of this mandrel is provided with an extension 21 having upwardly facing teeth 22 behind which the terminal portions 15 of the springs 1 3 are adapted to engage when the mandrel 1s forced downwardlythrough the rubber packer to expand the same.

The upper end of the mandrel 2O has a recess 23 receiving a reduced extension24 formed on the lower end of a soft metal Thissoft metal plug 25 has attached ythereto by a readily frangible or bend-able pin 26, the llower end of a tapered mandrel 27, the upper end of which is adapted for engagement with a means for lowering the same into the well, as indicated at 28.

In the use of the device, the tube 12 is made of 'such length that the packer will be properly spaced from the lower end of the well, and the entire assemblage is lowered into the well until the lower end of this tube seats upon the well bottom 10. Pressure is then applied from above, forcing the mandrel 20 downwardly until the rubber packer has been so firmly engaged with the walls that the resistance resulting will be suficient to enable. the mandrel 27 to release its anchoring meansA and move downwardly through the soft metal plug 25 to eX pand the same .into engagement with the walls of the casing. yVhile the anchorage afforded by the metallic packing would, in most instances, prove suiicient to prevent dislodgment of the mandrel 20, this mandrel is locked in its lowered position by the engagement of the spring fingers 15 with the teeth 22 of its extension 21. rIhus, both the lead plug and latching means serve to hold the packer 18 against vertical displacement in the well bore and the packers mutually serve to reinforce one another. In order to anchor the lower end of the mandrel 20 tothe plug structure during lower-` ing operations, the extension 21 of the mandrel is preferably provided with a head 29 seating about the edges of the opening of the annulus through which the extension passes when the tube 12 is moved downwardly a predetermined distance. The

above structure may be employed for plugging either oil; or gusqvvells or dry Wells in `Whielrno` o il or gas has been found.

Since the construction hereinbefore. set.

E forth is capable ofeeertainrangeof.Change.

and modification Without materially departing from the spirit of the inventioi-i,lk-,dofnot-V limit myself to suoli Specific structure eX` cept as hereinafter claimed.

1U I claim?- 1. A Well plugomprising u` seat,,eurubbery packer supported thereby,` w member` en-` geged. with the seat at itsl i upper i end and udeptedto engage the lowerl endeofia Well?` luborevwitli. its lewer, end,I mmandreldirected; through the rubbeupueker `nndlimitedV in itsi: upy turd movement.- With relation to the seat, a, softvk metal packen seated upon the@ upeperr; end of thelastnumed:mandrel and :e further;Y

llumendrelengaging theiupper end of Vtheusoft` metatl piaeke'r. y y i 2. A Welliplugleomprisingiwseal@ fr rubberfpuelrer suppprted therebygxamember engggedv3 with; the; Sent at its upper` end: and;

lfiudaptedd-toengegeffthelower end of afvvellt bore with'itsdowerend, ermandrel directed;l througlg the rub-bel). paekerg` endlianited inn its upward V; movement-` With relation: to; the

seat, u soft metal packer seated upon the upper end of the lestI nainedf mandrel and u a further mendrelfenga-ging the upper end of. the soft metal packer, said member und the first. named mandrel having eoacting means preventing` returnv movement of the first:nmnedunundrel when it has been forced 35 downwardly through the rubber packer.

3., A-iWelllplugicompriSing a seat, a rubber puolrer supported thereby, u member engaged withf tlieseat :rtf itey upper" endl and adaptedvto engage thlel lower endet zr- Well1 40 bore,` with` itef low er en d; ci l mundreh directed l through the. rubber. puel'erend .limited initsupwurd movement'Witlisrelution to tliesout, irse-ft metal puekfenn seated upon the upper end `ofitlre l named mandi-'eh' zi urtlrer45 mandrel `engeg ig `:the upper end foil Itliel soft' metal packer5V suidil member comprising` e tube sealed mite-,lower end,.spring'ngersf seeuredlatvtheir upper endsftothe Wellsaofl"y the-ytu-'besv and lruving inbent`- lower ende and i' 50 ann extension; for/the first named infandrelu` having upwardly' faoingteeth' for enga-gement by tlielowerendsocl said springs.

In ztestmoniy` lwhereof I l hereunto@ infix. my signature.. 1

N A THAN GOFN BRITTU N. 

